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geekhack Projects => Making Stuff Together! => Topic started by: yzdnegel on Tue, 21 December 2021, 16:30:40

Title: Have to have PCB in a position for teensy to work...?
Post by: yzdnegel on Tue, 21 December 2021, 16:30:40

So this summer I replaced my keyboard MCU with an teensy++ 2.0 and it worked fine. Then suddenly one row stopped working and I haven't gotten access to a soldering iron until now. So I opened my case while plugged in and tested it. It seems like the row only works in certain positions and seemingly random. I have no idea how to troubleshoot it as I don't really know where the problem could be. I resoldered the wires for that row and it still doesn't work. I've tried tilting it until it doesn't work anymore and tilt it back and record everything. I don't seem to see anything that really changes...

This is probably a far reach but I was wondering if anyone else has had the same problems or know where I should start...?

Title: Re: Have to have PCB in a position for teensy to work...?
Post by: nevin on Tue, 21 December 2021, 18:24:38

make sure you don't have a short anywhere, when it is put back together. (there's a couple wires that are stripped back pretty far or the insulation is melted and could be connecting to the adjacent wire/pin)

Title: Re: Have to have PCB in a position for teensy to work...?
Post by: yzdnegel on Wed, 22 December 2021, 15:19:45

I think that you were right that it was a short problem  :D

So I have added two rotary encoders and a screen above the arrows (tkl). They were shorting the row from the other side through some exposed wires from the old MCU (see the small soldering bits on the left side of the picture. It's the same on the other side under the rotary encoder). I solved it by putting some tape over the exposed wires.

Title: Re: Have to have PCB in a position for teensy to work...?
Post by: nevin on Wed, 22 December 2021, 17:02:17

glad you got it squared away.